Sumer was located in the Fertile Crescent between two rivers, the Euphrates River and the Tigris River. Sumerians settled in the southern part of Mesopotamia between 4500 B.C.E. and 4000 B.C.E. (National Geographic). Sumer was one of the first city-states to settle in Mesopotamia. Sumerians had many great innovations, including the origination of the first-ever writing system; cuneiform. They also created the wheel and the first set of coded laws. 

Sumer located in Mesopotamia 

Sumerian counting tokens

Merchants would use Cuneiform for their businesses. They'd use cuneiform to record their stocks and trade information. The merchants would also write down what their customers would be willing to trade them for. They would exchange livestock, materials, crops, and more. When exchanging these goods they would use tokens called counting tokens. These counting tokens helped indicate how much a person wanted to trade for (Puhvel). These were only some of the many reasons why cuneiform helped communicate trade among merchants (Mccall).  

Cuneiform was used to describe the religious activities of the Sumerians. They would use cuneiform to describe all of their gods and goddesses. Nisaba was associated with agriculture and grain, they would write in cuneiform as worship for her. The clay tablets with cuneiform described the gods and goddesses' stories. Over time, their stories would get mixed up, so what used to be about Nisaba would later on be about Nabu (Elvira Astoreca).

Cuneiform depicting the goddess Nisaba